Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
thu san » thuy san, thu ban, phu san
nang xa » lang xa, nang ma, mang xa
hieu va » lieu va, hieu qua
cac hoc » cach hoc, cac hop, bac hoc
va hanh » van hanh, va danh, ban hanh
cuu tre » cua tre, cau tren, cau treo
san ky » sang ky, van ky, dan ky
vi cuu » vi luu, vinh cuu

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

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