Perhaps you should try some spelling variations:
trinh ban » trinh han, trinh san, trinh dan
va trinh » van trinh, va tinh, lap trinh
doc thuc » hoc thuc, do thuc, hoc thuoc
su sach » so sach
hieu va » lieu va, hieu qua
ban cua » ban quan
thuc va » thuc vat, thuc dan, thuc day
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

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)) doc thuc va trinh ban 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)) doc thuc va trinh ban cua tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (vu sach)) ky lang xa hoi. ((hieu ve) or (hieu va)) doc thuc va trinh ban cua tre*.