Perhaps you should try some spelling variations:
cam viet » cham viet, ca viet, cao viet
hanh tai » thanh tai, hang tai, han tai
hanh lai » hanh lam, thanh lap, thanh loi
duc manh » suc manh, duc anh, duc minh
va thanh » gia thanh, ban thanh, va tinh
sach ty » sach y, sach tu, sach thu
va tham » van tham, va cham, va thuat
ty nang » ky nang, ty xang, ty hang
tu sach » thu sach, su sach, te sach
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: tu sach ty nang x hoi. hieu ((va tham) OR (va thanh)) duc manh ((hanh lai) or (hanh tai)) cam viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang x hoi. hieu ((va tham) OR (va thanh)) duc manh ((hanh lai) OR (hanh tai)) cam viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang x hoi. hieu ((va tham) OR (va thanh)) duc manh ((hanh lai) or (hanh tai)) cam viet".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang x hoi. hieu ((va tham) OR (va thanh)) duc manh ((hanh lai) or (hanh tai)) cam viet*.