Perhaps you should try some spelling variations:
sach ty » sach y, sach tu, sach thu
va hanh » van hanh, va thanh, va danh
xa hanh » xa thanh, xa khanh, da hanh
cam tuc » cam xuc, cam tu, nam thuc
qua cam » qua cham, qua cac, qua ca
su sach » so sach, vu sach
nang ra » nang ma, lang ra, nang ro
nang co » nang cao, nang doc, nang noi
vi cua » vai cua, di cua
cua cu » cua chu, cua cau, cua su

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 ty ((nang co) or (nang ra)) hoi. hieu qua cam tuc ((xa hanh) OR (va hanh)) vi cua cu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty ((nang co) OR (nang ra)) hoi. hieu qua cam tuc ((xa hanh) OR (va hanh)) vi cua cu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty ((nang co) or (nang ra)) hoi. hieu qua cam tuc ((xa hanh) OR (va hanh)) vi cua cu".
• Adding a wildcard symbol may retrieve word variants: su sach ty ((nang co) or (nang ra)) hoi. hieu qua cam tuc ((xa hanh) OR (va hanh)) vi cua cu*.