Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
nang mai » nang ma, nang tai, lang mai
mai hoi » mai khoi, dai hoi, lai hoi
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
cua tre » cua te, dua tren, cua thep
cuu tre » cau tren, cau treo
tu san » thu san, tu ban, tu can
san ky » sang ky, van ky, dan ky
va dam » van dam, va dao, va dau
dam tu » nam tu, cam tu, tam 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 san ky nang mai hoi. hieu va dam tu va hanh vi ((((cua tre) OR (cuu tre))) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu san ky nang mai hoi. hieu va dam tu va hanh vi ((((cua tre) OR (cuu tre))) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu san ky nang mai hoi. hieu va dam tu va hanh vi ((((cua tre) OR (cuu tre))) or (cua triet))".
• Adding a wildcard symbol may retrieve word variants: tu san ky nang mai hoi. hieu va dam tu va hanh vi ((((cua tre) OR (cuu tre))) or (cua triet))*.