Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
hieu van » hieu va, thien van, lieu va
chau tre » chay tren, chau tho, cau tra
tinh lai » tinh lao, tinh hai, minh lai
va tinh » may tinh
cam tuc » cam xuc, cam tu, nam thuc
van cam » van nam, van lam, van cau
ty dong » tay dong, tu dong, ly dong
ty song » tay song, ta song, ty nong
cho tre » cho thue, khoe tre
tuc va » thuc va, truc va, tuc xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sach ((ty song) or (ty dong)) xa hoi. hieu van cam tuc va tinh lai ((chau tre) OR (cho tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach ((ty song) OR (ty dong)) xa hoi. hieu van cam tuc va tinh lai ((chau tre) OR (cho tre))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach ((ty song) or (ty dong)) xa hoi. hieu van cam tuc va tinh lai ((chau tre) OR (cho tre))*".