Perhaps you should try some spelling variations:
pham trinh » pham tinh, pham minh, pham thanh
trinh vat » trinh van, trinh luat, sinh vat
hieu van » hieu va, thien van, lieu va
lam thuc » lam thuoc, am thuc, nam thuc
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » lang xa, nang ma, mang xa
van lam » van nam
cua tre » cuu tre, cua triet, dua tren
cua te » cua tu

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 ky ((nang xa) or (nang x)) hoi. hieu van lam thuc pham trinh vat ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang xa) OR (nang x)) hoi. hieu van lam thuc pham trinh vat ((cua tre) OR (cua te)).
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang xa) or (nang x)) hoi. hieu van lam thuc pham trinh vat ((cua tre) or (cua te))*.