Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
hoc sach » hoc sinh, hoc cac, hoc anh
hanh tai » hang tai, han tai, hinh tai
ly quang » le quang, vu quang
cac tuc » cac toc, cac tu, cac tac
cuc tre » duc tre, cua tre, cuu tre
hieu ve » hieu va, hieu van
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: hoc sach ((ly hang) OR (ly quang)) xa hoi. hieu ve cac tuc va ((hanh tai) or (thanh tai)) cuc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ((ly hang) OR (ly quang)) xa hoi. hieu ve cac tuc va ((hanh tai) OR (thanh tai)) cuc tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach ((ly hang) OR (ly quang)) xa hoi. hieu ve cac tuc va ((hanh tai) or (thanh tai)) cuc tre".
• Adding a wildcard symbol may retrieve word variants: hoc sach ((ly hang) OR (ly quang)) xa hoi. hieu ve cac tuc va ((hanh tai) or (thanh tai)) cuc tre*.