Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
van hanh » van thanh, ban hanh, van anh
hanh tai » thanh tai, hang tai, han tai
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
cam duc » cam xuc, cao duc, pham duc
duc van » duc va, duc tan, duc manh
cua tre » cua te, cuu tre, dua tren
ve cam » ve cham, ve cac, va cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu cac ky ((nang xa) or (mang may)) hoi. hieu ve cam duc van hanh tai ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu cac ky ((nang xa) OR (mang may)) hoi. hieu ve cam duc van hanh tai ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cac ky ((nang xa) or (mang may)) hoi. hieu ve cam duc van hanh tai ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: tu cac ky ((nang xa) or (mang may)) hoi. hieu ve cam duc van hanh tai ((cua tre) OR (cua triet))*.