Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
manh hanh » xanh hanh, danh thanh, minh thanh
cau tren » cu tren, dau tren, ca tren
dua tren » dung tren
tu tong » tu tuong, tu trong, tu dong
cac suc » cao suc, cac nuoc, cac cuoc
tu nong » tu dong, tu cong, tu tuong
hieu ve » hieu va, hieu van
ve cac » va cac, vien cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sach ((tu nong) or (tu tong)) xa hoi. hieu ve cac suc manh hanh vi ((cau tren) or (dua tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ((tu nong) OR (tu tong)) xa hoi. hieu ve cac suc manh hanh vi ((cau tren) OR (dua tren)).
• Adding a wildcard symbol may retrieve word variants: thuoc sach ((tu nong) or (tu tong)) xa hoi. hieu ve cac suc manh hanh vi ((cau tren) or (dua tren))*.