Perhaps you should try some spelling variations:
khan thong » khap thong, khau thong, nhan thong
tranh thuc » trinh thuc, trang thuc, thanh thuy
khong phap » chong phap, khong phai, phuong phap
phap thong » phap phong, phap chong, pho thong
can tranh » canh tranh, tan tran, van ranh
thuc hang » thuc hanh, thu hang, phuc hang
hang khoa » dung khoa
khoa khan » kho khan, khoa kham, khoa than
cac khong » cac phong, cat khong, cac phuong
sach bai » sach dao, cac bai, sach xa
bai thuc » bai thuoc, bao thuc, dai thuc
thuc cac » thuc cach, tuc cac, phuc cac
tu sach » thu sach, su sach, te sach
tu can » tu ban, tu cac, thu canh

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tu can tranh thuc hang khoa khan thong ) or ( tu sach bai thuc cac khong phap thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu can tranh thuc hang khoa khan thong ) OR ( tu sach bai thuc cac khong phap thong )).
• Adding a wildcard symbol may retrieve word variants: (( tu can tranh thuc hang khoa khan thong ) or ( tu sach bai thuc cac khong phap thong ))*.