Perhaps you should try some spelling variations:
trinh vat » trinh van, trinh luat, sinh vat
va trinh » van trinh, va tinh, lap trinh
su sach » so sach
vat cua » mat cua, bat cua, dat cua
coc tuc » coc luc, hoc thuc, doc thuc
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu van
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
vu sach » vu bach, vu khach
tuc va » thuc va, truc va, tuc xa

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) or (vu sach)) ky lang xa hoi. ((hieu ve) or (hieu va)) coc tuc va trinh vat cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu sach)) ky lang xa hoi. ((hieu ve) OR (hieu va)) coc tuc va trinh vat cua tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (vu sach)) ky lang xa hoi. ((hieu ve) or (hieu va)) coc tuc va trinh vat cua tre*.