Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
sach ky » sach y, sach ty, sach kem
hieu va » hieu qua
cam duc » cam xuc, cao duc, pham duc
duc van » duc va, duc tan, duc manh
cuu tre » cua tre, cau tren, cau treo
sac ky » cac ky, sai ky
vi cuu » vi luu, vinh cuu
x hoi » xa hoi, o hoi, x ho

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

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