Perhaps you should try some spelling variations:
hanh sinh » hanh tinh, hanh dinh, hinh sinh
thu tang » thu trang, thu thang, thu hang
sinh cua » manh cua, dinh cuu, sinh va
hieu van » hieu va, thien van, lieu va
sach thu » sach thue, sach thieu, sach tham
thuc dan » thuc hanh, thuc vat
tu sach » thu sach, su sach, te sach
tang ma » mang may, tang van
van cau » van dau, van hau, van chat
truc va » thuc va, thuc vat, trung va
cua te » cua tu
ma hoi » mai hoi, xa hoi, ma hoa

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 thu tang ma hoi. hieu van cau ((truc va) or (((thuc dan) or (hoc dan)))) hanh sinh cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach thu tang ma hoi. hieu van cau ((truc va) OR (((thuc dan) OR (hoc dan)))) hanh sinh cua te.
• Adding a wildcard symbol may retrieve word variants: tu sach thu tang ma hoi. hieu van cau ((truc va) or (((thuc dan) or (hoc dan)))) hanh sinh cua te*.