Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
cam truc » cau truc, nam truc, lam truoc
vu dinh » quy dinh
hieu ve » hieu va, hieu van
vu sach » vu bach, su sach, vu khach
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
ve cam » ve cham, ve cac, va cam
vi va » vi van, vai va, vu va

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach y ((nang xa) or (nang ma)) hoi. hieu ve cam truc ((vu dinh) or (may tinh)) vi va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach y ((nang xa) OR (nang ma)) hoi. hieu ve cam truc ((vu dinh) OR (may tinh)) vi va triet.
• Adding a wildcard symbol may retrieve word variants: vu sach y ((nang xa) or (nang ma)) hoi. hieu ve cam truc ((vu dinh) or (may tinh)) vi va triet*.