Perhaps you should try some spelling variations:
hanh hai » thanh hai, nhanh hai, hang hai
sach thu » sach thue, sach thieu, sach tham
thuc va » thuc vat, thuc dan, thuc day
ve cham » va cham, ve chat, vu cham
sach ty » sach y, sach tu, xach tay
hieu ve » hieu va, hieu van
cao hoc » co hoc, cho hoc, chat hoc
tuc va » truc va, tuc xa, duc va
hai va » hai van, thai va, hoi va
thiet » thieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ty) or (sach thu)) nang cao hoc. hieu ve cham ((tuc va) or (thuc va)) hanh hai va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach thu)) nang cao hoc. hieu ve cham ((tuc va) OR (thuc va)) hanh hai va thiet.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sach thu)) nang cao hoc. hieu ve cham ((tuc va) or (thuc va)) hanh hai va thiet*.