Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
hanh va » hang va, hanh vi
duoc va » duc va, duoc ma, duong va
sach ty » sach y, sach tu, xach tay
hieu ve » hieu va, hieu van
nang co » nang cao, nang doc, nang noi
co hoi » co hoc, co loi
ve tao » ve bao, de tao, ve tac
va cua » va chua, via cua, ca cua
cua cu » cua chu, cua cau, cua su

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc ((sach ty) or (sach thu)) nang co hoi. hieu ve tao ((duoc va) OR (nuoc va)) hanh va cua cu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc ((sach ty) OR (sach thu)) nang co hoi. hieu ve tao ((duoc va) OR (nuoc va)) hanh va cua cu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc ((sach ty) or (sach thu)) nang co hoi. hieu ve tao ((duoc va) OR (nuoc va)) hanh va cua cu".
• Adding a wildcard symbol may retrieve word variants: thuoc ((sach ty) or (sach thu)) nang co hoi. hieu ve tao ((duoc va) OR (nuoc va)) hanh va cua cu*.