Perhaps you should try some spelling variations:
hieu van » thien van, lieu va, hieu ve
nang tai » hang tai, sang tai, nang cao
tang tai » hang tai, dung tai, sang tao
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
cam loc » cam lo
vi cua » vai cua, di cua
loc va » hoc va, luc va
so sac » so sach, so dac
sac ky » cac ky, sai ky
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: so sac ky ((nang tai) OR (tang tai)) khoa. ((hieu van) or (hieu va)) cam loc va hanh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sac ky ((nang tai) OR (tang tai)) khoa. ((hieu van) OR (hieu va)) cam loc va hanh vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sac ky ((nang tai) OR (tang tai)) khoa. ((hieu van) or (hieu va)) cam loc va hanh vi cua te".
• Adding a wildcard symbol may retrieve word variants: so sac ky ((nang tai) OR (tang tai)) khoa. ((hieu van) or (hieu va)) cam loc va hanh vi cua te*.