Perhaps you should try some spelling variations:
cach khong » cach phong, cac phong, cach chung
hanh trinh » canh tranh, hanh chinh
trinh thuc » trinh tu, trinh thi
bach khang » bac thang, bach dang
sach thue » sach thu, sach thieu, sach tham
thue thuc » thuc thuc, thue thu, thu thuc
thuc cach » thuoc sach, truoc cach, thuc hanh
thuc bach » truc bach, thuoc sach, thuc hanh
khong he » khong khi, hong ha, khong _
thu hanh » thuc hanh, thu thanh, thuy hanh
khang he » khang kho, hang ha, bang he
tu sach » thu sach, su sach, te sach

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tu sach thue thuc cach khong he thong ) or ( thu hanh trinh thuc bach khang he thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach thue thuc cach khong he thong ) OR ( thu hanh trinh thuc bach khang he thong )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach thue thuc cach khong he thong ) or ( thu hanh trinh thuc bach khang he thong ))*.