Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc anh
cau phuc » chau phu, huu phuc, van phuc
hieu van » hieu va, thien van, lieu va
cau tren » cu tren, dau tren, ca tren
nang mai » nang ma, nang tai, lang mai
mai hoi » mai khoi, dai hoi, lai hoi
hoc cac » hoc cao
va dan » ca dan, va dao, va dau
dan va » doan va, dan ca, ban va
va cau » van cau, va cac, va dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((hoc sach) OR (hoc cac)) ky nang mai hoi. hieu van ((cau truc) or (cau phuc)) va dan va cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc sach) OR (hoc cac)) ky nang mai hoi. hieu van ((cau truc) OR (cau phuc)) va dan va cau tren*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc sach) OR (hoc cac)) ky nang mai hoi. hieu van ((cau truc) or (cau phuc)) va dan va cau tren*".