Perhaps you should try some spelling variations:
dau tren » dau tien, dat tren, dau tieng
hanh tai » thanh tai, hang tai, han tai
sach ly » sach y, sach lo, sach ty
duc tre » duoc tren, duc tien
va hanh » van hanh, va thanh, va danh
cac tuc » cac toc, cac tu, cac tac
co sach » bo sach, cuon sach, hoc sach
hieu ve » hieu va, hieu van
hang xa » hoang xa, hang ca, lang xa
tuc va » thuc va, truc va, tuc xa
ve cac » va cac, vien cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: co sach ly ((hang xa) or (hang va)) hoi. hieu ve cac tuc va hanh tai ((duc tre) or (dau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: co sach ly ((hang xa) OR (hang va)) hoi. hieu ve cac tuc va hanh tai ((duc tre) OR (dau tren)).
• Adding a wildcard symbol may retrieve word variants: co sach ly ((hang xa) or (hang va)) hoi. hieu ve cac tuc va hanh tai ((duc tre) or (dau tren))*.