Perhaps you should try some spelling variations:
hieu cach » hieu cac, chieu sach, hieu ca
dung chau » dung cau, dung cho, dung cua
dung chat » dung nhat, luong chat, dung cho
thong dam » thuong dam, thong nam, trong dam
dam nhanh » dam nhan, dam thanh, day nhanh
nhanh cau » nhanh cay, thanh chau, nhanh ha
hoc hieu » hoc thieu, hoc hien, doc hieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hieu cach - thanh ((dung chau) or (dung chat)) thong thong dam nhanh cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu cach - thanh ((dung chau) OR (dung chat)) thong thong dam nhanh cau.
• Adding a wildcard symbol may retrieve word variants: hoc hieu cach - thanh ((dung chau) or (dung chat)) thong thong dam nhanh cau*.