Perhaps you should try some spelling variations:
cua tre » cua te, cuu tre, cua triet
va hanh » van hanh, va thanh, va danh
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, nang cao
ma hoi » mai hoi, xa hoi, ma hoa
dan ky » van ky
san ky » sang ky, van ky, ban ky
cam ly » tam ly, cam ky, cam lo
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((san ky) OR (dan ky)) nang ma hoi. hieu va ((cam lyc) or (cam ly)) va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((san ky) OR (dan ky)) nang ma hoi. hieu va ((cam lyc) OR (cam ly)) va hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((san ky) OR (dan ky)) nang ma hoi. hieu va ((cam lyc) or (cam ly)) va hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((san ky) OR (dan ky)) nang ma hoi. hieu va ((cam lyc) or (cam ly)) va hanh vi cua tre*.