Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
van hanh » van thanh, ban hanh, van anh
sach thu » sach thue, sach thieu, sach tham
sach ty » sach y, sach tu, xach tay
duc van » duc va, duc tan, duc manh
ve cham » va cham, ve chat, vu cham
va cam » va cham, va cac, va cao
vi cua » vai cua, di cua
x hoi » xa hoi, o hoi, x ho

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

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