Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
luc ngan » luc nganh, luc nhan, luat ngan
sach ty » sach y, sach tu, sach thu
hang vi » hang va, hang di, khang voi
cu tren » tu tren, dua tren
ty nang » ky nang, ty xang, ty hang
ve cau » ke cau, va cau, le cau
ve cac » va cac, vien cac
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: thu sach ty nang x hoi. hieu ((ve cau) or (ve cac)) luc ngan ((hang vi) or (hanh vi)) cu tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ty nang x hoi. hieu ((ve cau) OR (ve cac)) luc ngan ((hang vi) OR (hanh vi)) cu tren.
• Adding a wildcard symbol may retrieve word variants: thu sach ty nang x hoi. hieu ((ve cau) or (ve cac)) luc ngan ((hang vi) or (hanh vi)) cu tren*.