Perhaps you should try some spelling variations:
"so sach bai thuc hanh khoa phu thong" » "so sach bai thuc hang khoa phu thong", "so sach bai thuc anh khoa phu thong", "so sach bai thuc hanh hoa phu thong", "so sach bai thuc hanh khoa phap thong", "so sach bai thuc hanh khoa khau thong", "so sach bai thuc hanh khoa phan thong", "so sach dao thuc hanh khoa phu thong", "so cac bai thuc hanh khoa phu thong", "so sach xa thuc hanh khoa phu thong", "so sach bai thuoc hanh khoa phu thong", "so sach bao thuc hanh khoa phu thong", "so sach dai thuc hanh khoa phu thong", "so sach bai thuc hanh khoa phau thong", "so sach bai thuc hanh khoa thu thong", "so sanh bai thuc hanh khoa phu thong", "bo sach bai thuc hanh khoa phu thong", "co sach bai thuc hanh khoa phu thong"
"so lanh dao thuc hanh khoa pho thong" » "so lanh dao thuc hang khoa pho thong", "so lanh dao thuc anh khoa pho thong", "so lanh dao thuc hanh hoa pho thong", "so lanh dao thuc hanh khoa he thong", "so lanh dan thuc hanh khoa pho thong", "so lanh dao tuc hanh khoa pho thong", "so lanh do thuc hanh khoa pho thong", "so lanh dao thuc hanh khoa khoa thong", "so lanh dao thuc hanh khoa phau thong", "so lanh dao thuc hanh khoa hoc thong", "so sanh dao thuc hanh khoa pho thong", "so danh dao thuc hanh khoa pho thong", "so lang dao thuc hanh khoa pho thong"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("so sach bai thuc hanh khoa phu thong") or ("so lanh dao thuc hanh khoa pho thong"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("so sach bai thuc hanh khoa phu thong") OR ("so lanh dao thuc hanh khoa pho thong")).
• Removing quotes may allow a broader search: (( so sach bai thuc hanh khoa phu thong ) or ( so lanh dao thuc hanh khoa pho thong )).
• Adding a wildcard symbol may retrieve word variants: (("so sach bai thuc hanh khoa phu thong") or ("so lanh dao thuc hanh khoa pho thong"))*.