Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
thanh va » thanh van, hanh va, thanh ha
su triet » su viet, su tien, ve triet
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa
va bao » va bai
bao bo » bac bo, ban bo, nao bo
bo va » bao va, do va, so va

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky nang ma hoi. hieu va bao bo va thanh va ((cua tre) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang ma hoi. hieu va bao bo va thanh va ((cua tre) OR (su triet)).
• Adding a wildcard symbol may retrieve word variants: su sach ky nang ma hoi. hieu va bao bo va thanh va ((cua tre) or (su triet))*.