Perhaps you should try some spelling variations:
hieu tieng » viet tieng, dien tieng, tiep tieng
thieu nien » thien nhien
sach ky » sac ky, sach y, sach ty
va hanh » van hanh, va thanh, va danh
cac dau » cac du, cac dai, cac mau
su sach » so sach, vu sach
sang ma » tang ma, nang ma, sang tao
ky sang » ky nang, ky dang, ky tang
ma hoi » mai hoi, xa hoi, ma hoa
vi cua » vai cua, di cua
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky sang ma hoi. ((hieu tieng) or (thieu nien)) ((cac dau) or (cac dan)) va hanh vi cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky sang ma hoi. ((hieu tieng) OR (thieu nien)) ((cac dau) OR (cac dan)) va hanh vi cua tu.
• Adding a wildcard symbol may retrieve word variants: su sach ky sang ma hoi. ((hieu tieng) or (thieu nien)) ((cac dau) or (cac dan)) va hanh vi cua tu*.